In recent years the solid state optically activated switch has received increasing attention because of its advantages in kilovolt pulser circuits. This interest stems from several unique properties of these switches not found in prior art switches used in pulser circuits. These optical switches comprise a bulk semiconductor usually of rectangular shape and can be intrinsic or doped. Since the semiconductor does not involve any p-n junctions, they can be scaled up in size to increase power handling capacity. A pair of contacts are applied usually to the same surface of the semiconductor wafer to define a gap between the contacts. The gap length is chosen to provide a hold-off voltage higher than the voltage to be switched, which is applied across the gap. This hold-off voltage is a function of the semiconductor material, its dopant and whether or not the gap surface has been passivated (or oxidized). Application of light to the gap area which is sufficiently energetic to cause the formation of charge carriers in the form of electron and hole pairs will rapidly close the switch and apply the high voltage to a load in series therewith. If the light covers the entire gap area there is no transit time limitation and the switching action is extremely fast. The switching action is accomplished with low jitter, and has the capability of high pulse repetition frequencies. Another important feature of these switches is the electrical isolation of the light signal from the switched power. One disadvantage of such an optical switch is the low current gain which results from the fact that approximately one photon of incident light is required to create one carrier pair. The present invention provides an optically activated switch of superior performance with higher current gain than prior switches of this type.